Elemental takes GPU-accelerated video processing to next level

April 7, 2010

When I spoke with Elemental Technologies' CEO Sam Blackman last fall, the next item on the startup's ambitious plan was real-time encoding.

This week, Elemental made good on Blackman's promise with the debut of Elemental Live, which the company claims is the first GPU-accelerated live encoding system that takes in a video stream and encodes it in real time for distribution over mobile networks. Elemental Live also is a GPU-accelerated live encoding server, which offers the flexibility of software encoding without the cost and complexity of CPU-based systems.

"Our customers want to support all devices, but they don't want to spend a lot to do it," Blackman said. "We are half the cost of competing solutions. Not only does our solution make [encoding] easier, it's half the cost. When people understand the value proposition of the GPU, they understand how we can make money at these prices."

Elemental Live will also be on display at NAB, in a four-screen demo featuring a TV, PC, iPad and iPhone.

GPU 101

The familiar CPU in your PC is a sequential processor: it does one thing at a time. A GPU, on the other hand, is a parallel processor: it does several things simultaneously.

"If you gave a CPU a book and asked how many times a certain word appears, the CPU would read from start to finish," is how NVIDIA manager Andrew Humber explained it. "A GPU would tear that book into thousands of chunks, and each one of those would get read at the same time." The bigger the job, the more processing cores you can add to handle the work. "You have the ability to do super-computing projects without a super computer," he said.

Elemental CEO Sam Blackman explained how parallel processing works with video. In digital video, pixels divide into macro blocks, said. Serial processors (CPUs) encode macro blocks one at a time sequentially. "With parallel processors, you can send all the macroblocks to the GPU at the same time, and stream processors can handle an entire frame simultaneously and even encode multiple streams at the same time." he said. "Plus, every time NVIDIA releases a new chip with more processors, our processing speed automatically increases."

GPUs also supply "greener" computing power. "Compared what you would need in a data center built on CPUs, it's an exponential difference," Humber said. "You can build a data center at 10 times less cost and 21 times less power."